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      Combinational analysis
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      <h1>
        Combinational analysis
      </h1>
      <p>
        All circuits fall into one of two well-known categories: In a <b>combinational circuit</b>, all circuit outputs are a strict <i>combination</i> of the current circuit inputs, whereas in a <b>sequential circuit</b>, some outputs may depend on past inputs (the <i>sequence</i> of inputs over time).
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      <p>
        The category of combinational circuits is the simpler of the two. Practitioners use three major techniques for summarizing the behavior of such circuits.
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        <img src="../../../../img-guide/analyze-type.png" alt="#########">
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      <ul>
        <li>logic circuits
        </li>
        <li>Boolean expressions, which allow an algebraic representation of how the circuit works
        </li>
        <li>truth tables, which list all possible input combinations and the corresponding outputs
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      </ul>
      <p>
        The <b class=refguide>Combinational Analysis</b> module of Logisim allows you to convert between these three representations in all directions. It is a particularly handy way of creating and understanding circuits with a handful of one-bit inputs and outputs.
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      <p>
        <b class=note>Note</b>: the combinatorial analysis is deactivated in Logisim-evolution. It is possible to reactivate with a command-line option.
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      <blockquote>
        <a href="ana-open.html">Opening Combinational Analysis</a><br>
        <a href="ana-table.html">Editing the truth table</a><br>
        <a href="ana-expr.html">Creating expressions</a><br>
        <a href="ana-gen.html">Generating a circuit</a>
      </blockquote>
      <p>
        <b>Next:</b> <a href="ana-open.html">Opening Combinational Analysis</a>.
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